Northern Andean Butterflies - Search and Research

90 Northern Andean Butterflies - Search and Research Mike Adams Photograph 3/ The high cloud-forests and moors of the northern Andes are a paradise for the biologist. Here in Colombia and Venezuela, where the great Andean chain fragments, each mountain range is like an island and each island has its own species ofanimals and plants. Colombia has five major mountain islands, three of them well over 5000 m high, separated from each other by deep valleys and low, narrow ridges; Venezuela has one 5000m chain emerging from Colombia's Eastern Cordillera. George Bernard (now a photographer) and I began our explorations of these mountains in 1971 and I have been there now six times. "Vith rucksacks, tent, butterfly nets and envelopes stored in boxes, we have scoured all six of the north Andean 'islands' for their high-altitude butterflies. Early on we discO\'ered several important things. firstly, as you climb the mountain-sides, the numbers of butterfly species diminish, but the proportion of endemic species increases dramatically. Secondly, virtually all the high-altitude butterflies require untouched cloud-forest or unculti\-ated moorland, and these - especially the former - are hard to find and hard to get to. Thirdly, ob\'iously few collectOrs haye bothered with the high ele\'ations, because cool rain and mist seem incompatible with butterfly life and most ofthe species up there are browns: so down they ha\'e gone, back to the mosquitoes and sandflies and the bright and beautiful butterflies of the lowlands, where the sun shines and your rucksack sticks to your back. Fresh (i'om university and Alpine butterflies, we chose to start with the Sierra ~e\'ada de Santa Marta, an isolated montane island ifever there was one - the area ofVorkshire, 5775 m high, rising plumb out ofthe Caribbean and surrounded by plains a few hundred metres above sea-level at the most. We bought a donkey - 'Balthazar Burro' - for our first attempt at the cloud-forests. For £10 we thought we had a bargain, but the efkminate, worm-ridden beast was a liability from the start, and on the first evening we were already carrying the rucksacks ourselves. Without a map and well and truly lost on the second day, we entered the territory of the Ica (or Arhuaco) Indians, tall, proud people wearing domed flaxen hats, woollen ponchos and coloured bags, chewing coca leaves and wary of strangers. The burro fell on' the path near Donachui and ended up on its hind legs on a ledge 2 m vertically below; in the hot sun - we were still at only about 1400m - we made a diagonal cut with machetes to guide the animal back. At Sogrome (1700m) we could see the cloud-forests above, but, the Indians told us, the route to Tromba was very dangerous and would take us three days; we were there in two hours' In idyllic Tromba, camped on the softest ofgrass beside a derelict lea hut on the banks of a sparkling torrent (2300m), we had our first taste of cloud-forest ~ORTHER~ ANDEAC'I BCTfERFLlES 91 browns. No books exist on Colombian butterflies, so we gave them our own nicknames and made our own judgements about what was interesting; we guessed that one ofour browns was rare, but little did we then know that it was not only a species new to science, but a new genus as well (Arhuaco ica Adams & Bernard). Getting to the uppermost forests on the western flank ofthe Santa Marta range was harder and we needed three attempts, foiled by losing our way, fever and lack ofwater (yes, this is possible in cloud-forest when the path relentlessly follows a knife-edged ridge and there is no-one around to tell you where the sources are!). But we finally made it, in two days from San Pedro de la Sierra, in 1972. Our prize up there, in the forest right at the tree-line, was another new species, Pedaliodes cebolLeta (meaning 'little onion' and named after the farmstead down below). Further up, in the grassy moors called the 'paramo', we found two species of browns: one of them was white, belonging to the genus Lymanopoda that in later years became almost an obsession - a biologist interested, as I am, in geographical distributions of related species and in their evolutionary histories could not ask for a more perfect group oforganisms to give him ideas and illustrate his theories. Our troubles in the Santa Marta massifwere by no means over. Trying to reach the paramo from the south-east, via Maruamaque, we were 'sent to Coventry' by dozens of Kogui Indians massing for a meeting in their religious centre, Chenducua, and were advised by a North American missionary to retrace our steps rapidly: top oftheir agenda was how to deal more forcefully with intruders bent on stealing their tribal heirlooms. Frankly, they would not believe that we were purely lepidopterists. The lea Indians were also flexing their muscles in 1972, determined to show that they should choose who enters their land, not the authorities down in non-Indian Valledupar; so, when we reached Donachui armed with all the proper documentation, the whole \'illage assembled in a long hut, men down one side, women d.own the other and we in the middle. facing the chiefshaman and a self-appointed political leader. Long speeches were delivered in pidgin Spanish, giving, we supposed. the reasons why we were not welcome and should heaq back down the valley (unless we paid some £200). A month later, we crept through Donachui long after dark, guided by a friendly Ica and his sturdy mule and stayed the night in one ofhis family huts at Sogrome along with his father, the local shaman. Once more we passed through Tromba and trudged up to the 4000m pass above it, camping at 3950m with Adalberto wedged in the tent between us. The identification ofour material (over 600 species from 6 months' collecting in the Sierra Nevada de Santa Marta) had to be attempted by ourselves, using the collections and literature at the British Museum ofNatural History (which, since 1975, has purchased all our butterflies from Colombia and Venezuela). It was then that we realised we had numerous new species - far too many to work on ourselves - and I began to concentrate on the browns, embarking on the first of our papers on the 'Pronophilini' ofthe northern Andes.' The intricacies of taxonomy are a far cry from the joys of searching for and catching the butterflies one is describing: The evolutionary relationships of the 13 endemic species are analysed. Three new genera, three new species, and four new subspecies are described. Four new synonymies are established, the status of 92 TH E .-\LPI:"EJOL'R:"..1,L three taxa revised, six new combinations made, and one original combination re-instated (from the abstract at the start ofour first paper). The white Lymarwpoda, for instance, had been named L. nevada in 1924. In 1927, another German named the same thing L. kruegeri, obviously unaware that Kruger himself had already described it. Then in 1931, Schultze called it Sabatoga nevadmsis - yet another name for the same species and put into a different genus to boot' Sortingout valid names - the first one always stands- is essential before you can begin to discuss the species' relationships in print and has taken up a lot ofmy non-teaching time since 1972. And if a species is new and undescribed, you cannot just arbitrarily give it a name and refer to it as such in your next paper: it has to be formally described. 'Forewing length: 33-35mm. Upperside unicolorous dark brown, with postdiscal black spots showing through from underside, on the forewing in cells Cu2 to Ml, and on the hindwing in cells Cu2 to R5 .. .' (Arhuaco ica). A halotype has to be selected and designated ('Holotype male, COLOMBIA: W. Sierra Nevada de Santa Marta, E. ofSan Pedro, 2700m, 6.viii.72 (M.J.A.),), and the full data given for all other specimens caught (the paratypes). The species' relationships need to have been established, its closest relatives determined by a variety ofcriteria, including the shapes of their males' genitalia. This is the fascinating but dry world of the museum man. But back now to the field' From the Santa Marta range, you can see the northernmost finger ofthe Andes proper - the Serrania de Valledupar, the highest part of the Sierra de Perija. Straddling the sensitive border with Venezuela, most of its few high-altitude human inhabitants are smugglers and renegades, and there are also persistent rumours about the savagery of the local Motilone Indians. No wonder no collector had ever been up there before! We reached its cloud-forest on a moonlit Christmas Eve, 1974, ready to sink into exhausted, thirsty sleep on the path when we spotted an abandoned homestead in a forest clearing. Our blistered feet prevented us from ascending above the lower cloud-forests that time, but we returned successfully a month later, using a 20-year-old mule ofgreat depend ability. On the Colombian side, above Manaure, the tree-line is low, down at 2800m, and the forest - bristling with mammals such as howler and spider monkeys, bears and a fierce blue carnivorous 'fox' - gives way to the 'Sabana Rubia', a gently-sloping, marshy expanse of 'pseudo-paramo', leading up to the border. Here, and in the lichen-encrusted uppermost forests at 3050m on the Venezuelan side, we found most of the 14 unknown species of browns that came our way in this amazing mountain range.l Condors circled overhead. Next on our itinerary was the Venezuelan Andean chain, the Cordillera de Merida.

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